In press working, a workpiece conveying apparatus is used for carrying continuously conveyed workpieces into or out of a pressing machine.
A known example of such a workpiece conveying apparatus is a workpiece conveying apparatus including: a pair of arm units; a workpiece gripping mechanism mounted between the respective distal ends of the arm units, and an elevating unit configured to move up and down the arm units, wherein a workpiece held by the workpiece gripping mechanism is conveyed by operating the arm units and the elevating unit (e.g. see PTL 1).
Another known example of such a workpiece conveying apparatus is a workpiece conveying apparatus including: a pair of arm units; a workpiece gripping mechanism mounted between the respective distal ends of the arm units; and an elevating mechanism for moving up and down the arm units with respect to a base substrate, wherein each of the arm units has a movable arm with which the respective distal ends of the arm units are joined so as to be movable with respect to each other and the workpiece gripping mechanism is supported via the movable arms (e.g. see PTL 2).
Recently, in press working, simultaneous conveyance and pressing of two workpieces has been performed with a view to improving productivity and streamlining.
A known example of such a workpiece conveying apparatus is a workpiece conveying apparatus including: a first movable arm having a first workpiece gripping mechanism; and a second movable arm having a second workpiece gripping mechanism, wherein the first movable arm and the second movable arm are joined so as to be movable with respect to each other (e.g. see PTL 3).